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This specification covers the engineering requirements for applying tungsten carbide/cobalt coatings to metal parts by the detonation process and the properties of such coatings.

Flame spray coating conditions, that allow the double layer coating by the same spray nozzle, have been determined for each layer. ...The authors, et al. have succeeded in the practical application of the abradable flame spray coating, used in aircraft engines for the prevention of air leakage and the improvement of efficiency, to automobile turbochargers for the first time in the world. ...In this paper, equations of relations between various flame spray coating conditions and the quality of coated film, which were derived from measured results, will be described.

It will be presented results of different coating systems, designed for each application. It is also discussed the coating engineering required due to the particular running conditions of each product. ...A lot of attention has been given to the development of new materials and coatings that not only minimize friction, but also improve wear resistance. Amorphous carbon (a-C:H, a-C:H:Me and a-C:H;X) known as DLC (Diamond-Like-Carbon) coatings have a high potential to fulfill these requirements, providing significant potential for a solution under these demanding service conditions. ...Amorphous carbon (a-C:H, a-C:H:Me and a-C:H;X) known as DLC (Diamond-Like-Carbon) coatings have a high potential to fulfill these requirements, providing significant potential for a solution under these demanding service conditions.

Currently there are three different types of bore solutions for small engines. 1) High silicon aluminum running with cast iron piston rings and a coated piston 2) Cast iron liner fitted to an aluminum block or cylinder 3) Nickel composite coating on an aluminum liner, cylinder, or block. A new method and apparatus has been developed to reduce the manufacturing tasks and costs of a bore solution. ...This new method involves turning a liner from aluminum and coating with nickel-silicon carbide. For the finish honing, an apparatus was developed that enables a liner to be honed for interference or clearance bonded fit into the block or the cylinder. ...The first part addresses the manufacturing and installation of liners and the second part gives engine designers some specifics of nickel ceramic composite electrolytic coatings.

We have investigated the use of commercially available thin and hard coatings (TiN, TiCN, TiAlN, and CrN) to mitigate the negative effects of EGR on wear. In friction and wear tests with the four-ball machine, we found that all the four coatings deposited on M-50 steel significantly reduced wear in EGR-contaminated oils when compared with uncoated M50 steel balls. ...In friction and wear tests with the four-ball machine, we found that all the four coatings deposited on M-50 steel significantly reduced wear in EGR-contaminated oils when compared with uncoated M50 steel balls.

Most piston rings and metallic sealing rings for modern application where running conditions are severe, require some form of coating to minimise abrasion and corrosion. The piston ring coating improves the life of engine as well as fuel efficiency. ...Wear test of the coating was conducted on pin on disc machine under dry conditions. The wear rate was calculated using mass loss methods on an electronic balance having least count of 1× 10−4 g. ...The wear rate of the coating was found to be increased with increase in load as well as sliding speed for the ion plating with the counter body of tungsten carbide but in the case of ion plating with the HCS & MS it is found to be decreased.

Among them, plasma transferred wire arc (PTWA) thermal spraying coating is becoming popular. Plasma electrolytic oxidation (PEO) coating is also proposed for increasing the wear resistance of aluminum alloy and reducing the friction between the cylinder and piston. ...In this work, a PEO coating with a thickness of ∼20 μm was prepared, and a high speed pin-on-disc tribometer was used to study the tribological behavior of the coating at oil lubricant conditions. Different surface roughness of the coating and a large range of the sliding speeds were employed for the tests. ...In this work, a PEO coating with a thickness of ∼20 μm was prepared, and a high speed pin-on-disc tribometer was used to study the tribological behavior of the coating at oil lubricant conditions.

This thick ceramic coating can be applied to automobile pistons by the new plasma-jet technology. Such coatings are practical and useful for increasing wear-resistance, heat-resistance and corrosion-resistance. ...Thick ceramic coating by plasma-jet spraying represents a novel and essential engineering tool which enables many products to be manufactured economically. ...A 1 mm thick alumina (A12O3) coating on an automobile piston was produced by plasma-jet spraying, thus surpassing the former thick alumina layer of 0.3-0.5 mm.

A discussion is presented on the various important features which need to be addressed in the design of viable thermal barrier coatings. The most economical way to ensure increased lifetime and operational safety of diesel engine components is to use a coating in order to improve surface properties. ...The most economical way to ensure increased lifetime and operational safety of diesel engine components is to use a coating in order to improve surface properties. By comparing the surface material properties required for engine operations and the properties of coating systems achieved until now, it is evident that the fracture toughness must be improved. ...By comparing the surface material properties required for engine operations and the properties of coating systems achieved until now, it is evident that the fracture toughness must be improved.

The first-ever application of a hydrogen-free diamond-like carbon (H free DLC) coating to a mass-production gasoline engine reduces friction between the cylinder bore and piston by 18%. ...Because low friction coating is effective in a thin oil film at a large area near top dead center (TDC). It is also found that the friction reduction effect is enhanced when low viscosity engine oil is used. ...DLC as a low friction coating is more effective in a thinner oil film. In this study, the adhesion strength of H-free DLC coating on piston rings is improved because of providing a smooth substrate, the new washing process and the optimized coating characteristics.

Army Tank Automotive Research & Development Engineering Center (TARDEC) has developed a low cost, durable ceramic composite cylinder bore coating for diesel engines operating under severe conditions. This bore coating is a ceramic composite consisting primarily of Iron Oxide, Iron Titanate and Partially Stabilized Zirconia. ...It is applied by unique chemical thermal bonding technology developed at Adiabatics, Inc. and is referred to as Low Temperature Iron Titanate (LTIT). This coating has been tested against a wide range of cylinder bore treatments ranging from hard chrome plate to hard Nickel Silicon Carbide (NikaSil) and found to provide a superior sliding wear surface. ...It is superior because it is compatible against most common piston ring materials and coatings. As compared to other liner treatments, it displays superior running in or break in performance of the ring against the cylinder liner and yields significantly better wear rates under high wear extreme loading engine operating conditions.

At first, the ice adhesion shear stress to the surface was investigated experimentally for some of ice-phobic coatings. Then, the icing test of rotating fan in corporate with the ice-phobic coating blades was conducted using a simple model axial fan as an earlier step of experimental study using real fan blade of aircraft engine. ...In the present study, the purpose is to investigate surface coating effect on protection of icing to axial fan blade. At first, the ice adhesion shear stress to the surface was investigated experimentally for some of ice-phobic coatings. ...From these tests, anti/de-icing capability of some typical ice-phobic coating for axial fan blade was confirmed in the icing test using a simple model axial fan. Furthermore, it was confirmed by the icing test that the surface coating effect on protection of icing to axial fan blades was correlated to the ice adhesion shear stress of coating surface.

Our approach is to apply a DLC coating on the piston running against an aluminum-390 bore thus eliminating the iron liners in a standard piston/bore system. ...Experimental data, using a pin-on-disk tribometer under unlubricated test conditions, indicate that the performance of the DLC coating against aluminum 390 exhibits superior friction resistance compared to aluminum-390 against cast iron; the latter material couple representing the materials currently being used in production for the piston/bore application. ...Moreover, by thermally cycling the DLC coatings we show that improved friction and wear properties can he maintained to temperatures as high as 400°C.

This Paper presents comparative analysis of heat release in base line and insulated (Piston crown with plasma sprayed zirconia coating) diesel engine. The coating system affects the fuel consumption, the power and the combustion efficiency, pollution contents and the fatigue lifetime of engine components. ...Experimental research of insulated diesel engine incorporating thermal barrier coating (TBC) has produced controversial result. Some publications report that engine efficiency increases with insulation, while others argue that efficiency decreases. ...Several disadvantages such as producing nitrogen oxides also exist when a coating system is used. In this Paper, all effects, advantages and disadvantages of thermal barrier coatings are investigated based on experimental result.

The GPF is used under higher temperatures than diesel engine and the amount of particulate matter (PM) is also less than in a diesel engine, so GPF coating in-the-wall is an effective way to reduce the pressure drop. Also, it was found that a deep coating into the wall helps maintain larger pore diameters and enlarges the flow route of the gas. ...Also, it was found that a deep coating into the wall helps maintain larger pore diameters and enlarges the flow route of the gas. ...At the same time, coating on-the-wall also improved the PM filtration efficiency. This technology is utilized for diesel engine particulate filters (DPF) as well.

In this paper, a single cylinder engine with variable expansion to compression ratio (ER/CR) was analyzed for its performance when copper coating is done on the surface of cylinder head - piston combination. Copper element that can promote pre-flame reaction was coated on the surface of cylinder head and piston. ...Due to the catalytic effect of copper coating it was found that for the copper coated EE engine, the brake thermal efficiency was improved by 4% compared to standard engine operating at same conditions.

Thermal barrier coatings (TBCs) were used to simulate adiabatic engines with the intention not only for reduced in-cylinder heat rejection and thermal fatigue protection of underlying metallic surfaces, but also for possible reduction of engine emissions. ...The insulation of the combustion chamber with this coating, which is ceramic based, influences the combustion process and hence the performance and exhaust emissions characteristics of the engines. ...A plasma sprayed thermal barrier coating was deposited on top of a piston for a Diesel engine and its effect on the engine performance is studied.

Special coatings are being developed and tested to contend with the effects of dust on the lunar surface. ...Special coatings are being developed and tested to contend with the effects of dust on the lunar surface. These coatings will have wide applicability ranging from prevention of dust buildup on solar arrays and radiator surfaces to protection of EVA space suit fabrics and visors. ...We have started preparing abrasion-resistant transparent conductive coatings ∼40 nm thick were formed by co-deposition of titanium dioxide (TiO2) and titanium (Ti) on room-temperature glass and polycarbonate substrates using two RF magnetron sputtering sources.

At Argonne National Laboratory, we recently developed low-friction amorphous carbon coatings with exceptional tribological properties. The present study evaluates the scuffing performance of three variations of the carbon coating deposited on H-13 steel surfaces and lubricated with base-stock and fully formulated synthetic Poly-alfa-olefin (PAO) lubricants. ...The present study evaluates the scuffing performance of three variations of the carbon coating deposited on H-13 steel surfaces and lubricated with base-stock and fully formulated synthetic Poly-alfa-olefin (PAO) lubricants. ...Using a ball-on-flat contact configuration in reciprocating sliding, we found that although the coatings reduced friction slightly, they increased scuffing resistance significantly when one of the sliding surfaces was coated when compared to uncoated steel-on-steel contact.

CrN-PVD is a coating largely applied to European and Japanese applications, due to its excellent tribological properties, i.e. reduced friction, higher scuffing resistance and higher wear resistance. ...Particularly for oil control rings it will be presented the friction reduction potential through the application of PVD coating and the design improvements that it enables. This way, the reduction on mechanical losses would come from both material and design in order to contribute on CO2 reduction.